Original ContributionsA comparison of bowel preparations for flexible sigmoidoscopy: oral magnesium citrate combined with oral bisacodyl, one hypertonic phosphate enema, or two hypertonic phosphate enemas1
Introduction
Flexible sigmoidoscopy is among the most common outpatient procedures performed by primary care physicians (1). Good visualization of the colonic mucosa is essential to an adequate procedure. Numerous bowel preparations have been used over the years. Previous studies had not identified a clearly superior method and several found no significant difference between one- or two-enema preparations 2, 3, 4, 5, 6, 7. However, two studies published over the past 2 years have shown better preparation methods.
One study showed a significant improvement in preparation quality and patient comfort using a combination of oral magnesium citrate and oral bisacodyl over a hypertonic phosphate two-enema preparation (8). Another study recently published from several of our authors compared magnesium citrate plus two hypertonic phosphate enemas, versus one- and two-enema preparations (9). It also showed a significant quality improvement with the two-enema/magnesium citrate preparation over the enemas alone, with no difference seen between one- or two-enema preparations. There was no significant difference in patient comfort ratings between the groups.
Based on these studies, we surmised that the addition of oral magnesium citrate to either an oral cathartic agent or enemas improved bowel preparation quality. The remaining question we attempted to answer is whether enemas, either one or two, combined with magnesium citrate, are superior to a completely oral preparation of magnesium citrate and oral bisacodyl.
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Materials and methods
All patients undergoing flexible sigmoidoscopy in the Madigan Army Medical Center (MAMC) Adult Primary Care Clinic between July 1, 1997 and July 10, 1998 and in the Walter Reed Army Medical Center (WRAMC) Gastroenterology Clinic between May 1, 1998 and August 7, 1998 were invited to participate. Exclusion criteria included undergoing the procedure without preparation, dementia, a history of serum creatinine >2.0 mg/dl, congestive heart failure, a history of hyperphosphatemia or hypermagnesemia,
Results
More than 95% of eligible patients enrolled and 89.3% of enrolled patients completed the study. Most of those patients not completing the study decided not to have the procedure, moved from the area, or had other medical testing supercede the procedure. Five patients violated blinding by identifying their preparation to the endoscopist (oral bisacodyl/citrate = 3, one-enema/citrate = 1, two-enema/citrate = 1). These patients were excluded from the preparation quality analysis. Study patients in
Discussion
Our study found no differences in preparation quality between an exclusively oral regimen (bisacodyl/citrate) and a combination of magnesium citrate with either one or two enemas. Patient satisfaction and tolerance of all three preparations was high, though patients clearly preferred the oral regimen to the enema regimens. There was a stepwise decrease in patient-reported preparation difficulty from the double-enema preparation, to the single-enema, and the exclusively oral regimen. This
Conclusions
In summary, clinicians performing flexible sigmoidoscopy should strongly consider the use of bowel preparations including magnesium citrate, in combination with either one hypertonic phosphate enema or oral bisocodyl. The use of these regimens would improve mucosal visualization, which would allow better polyp screening and reduce the number of repeat procedures due to poor preparations. The use of magnesium citrate and oral bisacodyl could also reduce nursing time. Such benefits could save
Acknowledgements
We thank Laurie Harrell, R.N. Without her assistance and dedicated vigilance as the protocol nurse, this study would not have been completed. We are indebted to her and cannot express our appreciation enough.
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2006, Essential Clinical ProceduresDecreased efficacy of polyethylene glycol lavage solution (Golytely) in the preparation of diabetic patients for outpatient colonoscopy: A prospective and blinded study
2001, American Journal of GastroenterologyCitation Excerpt :Although diabetes mellitus is known to be associated with disturbances in bowel motility (11, 12), there are no studies specifically addressing whether patients with diabetes undergoing colonoscopy require a more vigorous colonic preparation than do those without diabetes. In a recent study comparing magnesium citrate versus phosphate enema bowel preparations for flexible sigmoidoscopy, however, diabetic patients were less likely to have preparations rated as excellent or good (13). The present study was designed to compare, in a prospective and blinded fashion, the efficacy of a standard outpatient Golytely preparation in diabetic versus nondiabetic patients.
Resident participation in flexible sigmoidoscopy does not affect patient satisfaction
2000, American Journal of GastroenterologyCitation Excerpt :Because of the nonrandom nature of patient assignment to a resident, propensity score analysis was performed to assess the need to adjust for potential confounders (25, 26). These data were collected as part of two clinical trials comparing different bowel preparations for flexible sigmoidoscopy (27, 28). As there was no effect of the trial interventions on the outcomes reported in this study, confirmed in multivariate analyses, no adjustment for study wing was made.
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The views expressed in this article are those of the authors and should not be construed to represent in any way those of the Department of Defense or the Department of the Army.